Traction device



Aug. 28, 1956 J. w. BOUGHTON TRACTION DEVICE Filed Dec. '7, 1953 a v 7 52722/ 672 for";

United States Pat I2,760,626 'mrcnonusvren .elai'ns W.=-Bo'u"ghton,'Chicago, IlL, 'assignor to Electric -Parts Gorporation, @hicago, Ill.,a corporation -'of Illi- -nis invention "relates to traction devicesadapted "for of tubing, hose. -or--strip stock. ltrmay also serve as adrive for various types of machines, or forrnoving a "wire-o1- tapethrough "ainagnetie'recording machine.

Briefly, the present invention comprises two endless belts extendingaround a plurality of sheaves, the belts converging into the annulargroove of one sheave to frictionally engage therein the wire, or othermaterial to be moved, and the belts diverging from the groove of saidone sheave at a point circumferentially spaced from their point ofconvergence to free the wire for movement away from the sheave.

Traction devices heretofore employed for moving wire and the likeusually comprised a pair of coacting nip rolls which merely engagepoints at opposite sides of the wire. The present invention contemplatesthe provision of a traction device in which line contact frictionalengagement is provided along three sides of the material being moved toinsure adequate traction without damage to the material.

This invention further contemplates the provision of a traction devicein which the several parts thereof are formed and arranged to facilitatethreading of a length of flexible material thereinto for movementtherethrough.

Another object of the invention resides in the provi sion of a tractiondevice which is relatively simple and inexpensive in construction andreliable in operation.

This invention embodies other novel features, details of constructionand arrangement of parts which are hereinafter set forth in thespecification and claims and illustrated in the accompanying drawings,wherein:

Fig. 1 is a top plan view illustrating a traction device embodyingfeatures of the invention.

Fig. 2 is a longitudinal sectional view taken along the line 22 of Fig.1.

Fig. 3 is an enlarged detail sectional view taken along the line 33 ofFig. 2.

Fig. 4 is a detail sectional view, corresponding to Fig. 3, illustratinga modified form of the invention.

Fig. 5 is a detail sectional view, corresponding to Fig. 3, illustratinganother modified form of the invention.

Referring now to the drawing for a better understanding of the inventionand more particularly to Figs. 1 to 3 therein, the traction device isshown as comprising shafts 6, 7 and 8 journaled for rotational andnon-axial movement in suitable bearings provided in side frames 9-9, theshaft 6 being connected to an electric motor or other source of power(not shown).

A driving sheave 11 is keyed to the shaft 6, a pair of axially spaceddriven sheaves 12 and 13 are keyed on 2,760,626 l l atented' wu'g.28,1956

ice

the diiVenshaft Zand 'a-pair 'oflaxially =spacedtensidn adjusitmer'it'sheaves 14 and 16 are keyedonthe shaft ll.

Apair-of-endless belts I7 and 18 are "mounted on the sheaves 1' 2 -'14and I3'1'6, respectively, and "converge therefrom into the annular"groove '19 of the driving sheave 1'1. 'As'illustr'ated in thedrawingftlie upperiii lits of the belts 17 'and' T8 convergefromtheir-respective .20 For example, the traction device is.adapted-for:-use in' sheave toward their res ective"tension'aiijustmentslreaves 1'4- and I6.

*As viewed in transverse's'e'ction "inFigJZftIie annllIar groove -19ofthe"drivingsheaveffl'is de ned bybpposed, axially spacedannu1ar-rider-miracles 21 21 convergin inwardly *tow art! "and merginwith a circular "inner-aurface Z22, and the endless 'blts "17 andaref'of "circular crosssection for enga ement 'between *tiiesiue'surfaces n -oi "and biased -towar'dthe inner-surface 22, fbyz tl ietensionfatljustment sheavesfl l and to causewiref w, or the like, "to beengaged between the "belts "and against {the innei- -surf ce'z'r-throughoutaportion dfthecircurhings 2323 adjustablymounted*in"slots"24 24"forlned in the side frames 9-9, the bearingsbeing adjustably positioned within their respective slots by means ofadjustment screws 26-26 threaded through bosses 27-27 on the side framesto increase or decrease the tension applied to the endless belts.

In the operation of the traction device thus shown and described, thewire W is frictionally engaged between the surface 22 of the drivingsheave and the endless belts throughout a portion of the circumferenceof said surface and is progressively fed through the device fordischarge to any desired place, such as a hopper. It will also be notedthat the clamping force exerted by the endless belts against the wiremay readily be varied by means of the adjustment screws 26-46.

Fig. 4 illustrates a modified form of the invention in which thetraction device is provided with a pair of conventional endless belts31-31 of the type commonly referred to as V-belts, the belts beingformed and arranged to engage a wire W against the inner surface 22 of agroove 19 formed in a driving sheave 11. This form of the invention isotherwise similar to the form heretofore shown and described.

Fig. 5 illustrates another modified form of the invention in which thetraction device is provided with a pair of endless belts 3232 oftriangular section mounted within the grooved driving sheave 11 toengage a wire W. This form of the invention is otherwise similar to theform heretofore described in connection with Figs. 1 to 3 in thedrawing.

While this invention has been shown in several forms, it is obvious tothose skilled in the art that it is not so limited, but is susceptibleof various changes and modifications without departing from the spiritand scope of the claimed invention.

I claim:

1. In a traction device for moving a flexible element, a rotatabletraction sheave having an annular groove defined by inwardly convergingside surfaces and a circular inner surface, two endless driving beltsengaged side by side between the side surfaces of said groove to clampthe flexible element against a segment of the circumference of saidinner surface, said belts diverging from opposite sides of said sheavein planes substantially tangent to said sheave.

2. In a traction device for moving a flexible element, a rotatabletraction sheave having an annular groove defined by inwardly convergingside surfaces and a circular inner surface, two endless driving beltsengaged side by side between the side surfaces of said groove to clampthe flexible element against a segment of the circumference of saidinner surface, a pair of driven sheaves I engaged by related belts, saiddriven sheaves being axially spaced from said traction sheave andlaterally spaced from each other, a pair of axially spaced belttensioning sheaves engaged by relatedbelts, said belts converging v fromtheir respective driven sheaves for side by side' abutting engagingwithin said traction sheave.

3. In a traction device for moving a flexible element, a rotatabletraction sheave having an annular groove defined by inwardly convergingside surfaces and a circular inner surface, two endless driving beltsengaged side by side between the side surfaces of said groove to clampthe flexible element against a segment of the circumference of saidinner surface, a pair of driven sheaves engaged by related belts, saiddriven sheaves being axially spaced from said traction sheaves andlaterally spaced from each other one on each side of the tractionsheave,

: respective tensioning sheaves.

4. In a traction device for moving a flex'ibleelernent, a rotatabletraction sheave having an annuiar groove defined by inwardly convergingside surfaces and a circular inner surface, two endless driving beltsengaged side by side between the side surfaces of said groove to clampthe flexible element against a segment of the circumference of saidinner surface, a pair of driven sheaves engaged by related belts,saiddriven sheaves being axially spaced from said traction sheave andlaterally spaced from each other one on each side of the tractionsheave, a pair of belt tensioning sheaves engaged by related belts, saidbelt tensioning sheaves being axially spaced from said traction sheaveand laterally spaced from each other one on each side of said tractionsheave, said belts converging from their respective driven sheaves forside by side abutting engaging within said traction sheave, said beltsdiverging from said traction sheave toward their respective tensioningsheaves, and means to adjust the position of said tensioning sheavesrelative to said traction and driven sheaves to vary the clamping forceexerted by said belts against said element.

References Cited in the file of this patent UNITED STATES PATENTS BaconOct. 18, 1949

